Improvement in propelling vessels



PATENT OFFICE.

MATTHEW K. WILDMAN, OF BROOKLYN, NEW YORK.

IMPROVEMENT" IN PROPELLING VESSELS.

Specification forming part of Letters Patent No. 122,301, dated December 26, 1871.

To all whom t may concern:

Beit known that I, MATTHEW K. WILDMAN, of the city of Brooklyn, in the county of Kings and State of N ew York, have invented a new and useful Improvement in Means of Propulsion Applicable to Vessels for Navigating 'Canals and other Waters; and I do hereby declare that the following' is a full, clear, and exact description, reference being had to the accompanying drawing forming part of this specification, and in which- Figure 1 represents a vertical longitudinal section of a boat constructed in accordance with my improved means of propulsion, and having the same applied to it. Fig. 2 is a transverse section taken as indicated by the line .r a: in Fig. l. Fig. 3, a horizontal section through the line y y. Fig. 4 is a view on a larger scale of a divided propeller in part7 with its connecting gearing.

Similar letters of reference indicate corresponding part-s throughout the several figures.

My invention is designed more especially for boats or vessels to be used on canals and other narrow waters, in which, among other objects to be gained, it is desirableto guard against the washing of the banks by the action cfa propeller applied to the boat, and worked by steam or other motive power. To this and other ends my invention `consists of -two reversely-pitched screw-propellers, geared to rotate in opposite directions, one in front of the other, and so that the rear one revolves faster than the forward one, which pre` vents clicking of the latter by back-water. The boat also has its rudder arranged within the rear end of the water-course or passage between the two lon gitudinally-arran ged hull sections, and is preferably constructed so that it may be turned to wholly close the passage-on either side of the boat, whereby increased facility is. afforded for steering or turning the boat.

Referring to the accompanying drawing, A

" represents the hull of a boat suitable for navigating canals and other narrow waters, and which may be formed with straight or iiat sides on its exterior. The lower portion of the boat is divided into two hull sections, B B, constructed to form a longitudinal water-course or passage, C, between them, and extending centrally through the boat from bow to stern. This passage C, as

formed by the inner walls of the hull sections B B, is of peculiar construction, being made to correspond with or approximate the ordinary shape r of the bow and run of a boat as usually made, and havin gwhat may be termed two sub bows and two sub sterns, so that on a propeller being arranged between said hull sections, andopcrate to take the water in front and project it in rear, the water will be gradually drawn in from opposite sides in front and concentrated on the propeller and be discharged in a graduallywid` ening or spreading manner in the rear, by reason of the laterally-flaring shape of the passage C at the bow and stern. The water thus forced back` takes the place of that displaced by the boat, free from .that excessive agitation and lateral disturbance, occasioning injury to the banks, that takes place when a wheel or propeller is used to throw the water in a straight line or lines in rear of the boat. The propeller is preferably divided or made to consist of two spiral shafts or screws, D D, arranged, one in advance of the other, within the passage C, and with their screwblades set in reverse directions, so that the one screw is right-handed and the other left-handed. These screws or propellers are geared to rotate in reverse directions at different velocities, and so that the rear propeller D moves faster than the forward screw or propeller D, whereby the rear propeller relieves the. forward one, and choking by backwater is avoided. This reverse ac-V out of the way and protected, as in the case of a canal-boat, when passing through locks, and said rudder provided with an inner or reverse and additional wing, d, that produces in a measure a counterbalancing actionof the water on the rudder, which is of such proportions that when fully turned to the right or to the left it is made to re..

strict'the. outiiow from the passage C to one side only ofthe boat by the contact or approximate position of the wing d with the one rear fiaringside ofthe passage C. This materially assists in the steering of the vessel, and adds to the efficiency of the propeller for steering purposes.

What is here claimed, and desired to be secured by Letters Patent, is-

1. The propellers D D', arranged o ne in ad- Vance of the other, and of opposite pitch, as described, made to rotate in reverse directionsat diierent velocities, by means of the differential gear b blr and c, essentially as herein set forth.

2. The. arrangement of the` rudder E within the rear endk of the: passage C, between the hull sections, so asto be capable of Wholly closing either side ofthe outlet of said passage, substantially as shown and described, for the purpose set forth. Y Y

MATTHEW. K. WILDMAN.

Witnesses FRED. HAYNEs,

FERD. TUscH. (139) 

